Navigation Links
Researchers map how staph infections alter immune system
Date:7/13/2009

DALLAS July 14, 2009 Infectious disease specialists at UT Southwestern Medical Center have mapped the gene profiles of children with severe Staphylococcus aureus infections, providing crucial insight into how the human immune system is programmed to respond to this pathogen and opening new doors for improved therapeutic interventions.

In recent years, much research has focused on understanding precisely what the bacterium S aureus does within the host to disrupt the immune system. Despite considerable advances, however, it remained unclear how the host's immune system responded to the infection and why some people are apt to get more severe staphylococcal infections than others.

By using gene expression profiling, a process that summarizes how individual genes are being activated or suppressed in response to the infection, UT Southwestern researchers pinpointed how an individual's immune system responds to a S. aureus infection at the genetic level.

"The beauty of our study is that we were able to use existing technology to understand in a real clinical setting what's going on in actual humans not models, not cells, not mice, but humans," said Dr. Monica Ardura, instructor of pediatrics at UT Southwestern and lead author of the study available online in PLoS One, the Public Library of Science's online journal. "We have provided the first description of a pattern of response within an individual's immune system that is very consistent, very reproducible and very intense."

The immune system consists of two components: the innate system, which provides immediate defense against infection; and the adaptive system, whose memory cells are called into action to fight off subsequent infections.

In this study, researchers extracted ribonucleic acid from a drop of blood and placed it on a special gene chip called a microarray, which probes the entire human genome to determine which genes are turned on or off. They found that in children with invasive staphylococcal infections, the genes involved in the body's innate immune response are overactivated while those associated with the adaptive immune system are suppressed.

"It's a very sophisticated and complex dysregulation of the immune system, but our findings prove that there's consistency in the immune response to the staphylococcus bacterium," Dr. Ardura said. "Now that we know how the immune system responds, the question is whether we can use this to predict patient outcomes or differentiate the sickest patients from the less sick ones. How can we use this knowledge to develop better therapies?"

Researchers used blood samples collected between 2001 and 2005 from 77 children 53 hospitalized at Children's Medical Center Dallas with invasive S. aureus infections and 24 controls. The control samples were collected from healthy children attending either well-child clinic or undergoing elective surgical procedures. Children with underlying chronic diseases, immunodeficiency, multiple infections, and those who received steroids or other immunomodulatory therapies were excluded from the study.

The children ranged in age from a few months to 15 years and included 43 boys and 34 girls. Those with S. aureus infections both methicillin-resistant (MRSA) and methicillin-susceptible (MSSA) were matched with healthy controls for age, sex and race. The researchers also characterized the extent as well as the type of infection in each patient to make sure that the strain of bacteria didn't influence the results.

Dr. Ardura stressed that more research is needed because the results represent a one-time snapshot of what's going on in the cell during an invasive staphylococcal infection.

"The median time to get the blood sample was day four because we wanted to make sure the hospitalized children had a S. aureus infection, and its takes four days to have final identification of the bacterial pathogen," she said.

The next step, Dr. Ardura said, is to study those dynamics in patients before, during and after infection. They also hope to understand better how various staph-infection therapies affect treatment.

"This is a very important proof-of-concept that the information is there for us to grab," Dr. Ardura said. "Now we have to begin to understand what that data tells us."


'/>"/>

Contact: Kristen Holland Shear
kristen.hollandshear@utsouthwestern.edu
214-648-3404
UT Southwestern Medical Center
Source:Eurekalert  

Related medicine news :

1. Researchers identify individuals at risk for developing colon cancer
2. Arizona researchers to sequence West African rice strain
3. Six Researchers to Receive Prestigious Awards from the American Society of Hematology
4. Mount Sinai researchers find new Alzheimers disease treatment promising
5. Researchers consider herd movements to help eradicate bovine TB
6. Pre-cessation patch doubles quit success rate: Researchers call for labeling changes
7. Researchers identify potential patient safety risks among methadone maintenance treatment patients
8. Purdue researchers create prostate cancer homing device for drug delivery
9. Moles and melanoma -- researchers find genetic links to skin cancer
10. Australian researchers identify genes that cause melanoma
11. Researchers find possible environmental causes for Alzheimers, diabetes
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Researchers map how staph infections alter immune system
(Date:3/27/2017)... ... March 27, 2017 , ... Adding to its expanding ... of Medicine and NEJM Journal Watch, announces the release of NEJM Knowledge+ ... a panel of pediatricians from leading medical centers. The content was then reviewed ...
(Date:3/27/2017)... Little Rock, AR (PRWEB) , ... March 27, 2017 , ... ... the CMSA National Board of Directors on June 30, 2017. CMSA’s membership has ... board. In addition to our current Military Advisory position, a new VA Advisory position ...
(Date:3/27/2017)... ... 27, 2017 , ... Osteitis pubis may be commonplace and ... it occurs when the muscles around the pelvis become inflamed. Over time, untreated ... torso, as well as accompanying tenderness and weakness. Without proper intervention, it can ...
(Date:3/27/2017)... PA (PRWEB) , ... March 27, 2017 , ... ... business simulation -centric training, today announced the launch of a new research ... strategy, having the skills needed to execute that strategy, and the actual success ...
(Date:3/27/2017)... ... March 27, 2017 , ... Kwalu, ... second year in a row; they are the recipient of the prestigious “Best ... voted on the award at Design Connections 2017. Top A&D professionals from leading ...
Breaking Medicine News(10 mins):
(Date:3/27/2017)... SAN FRANCISCO , March 27, 2017 ...  is expected to reach USD 16.0 billion by 2025, ... Inc. The growing prevalence of chronic diseases is anticipated ... clinical chemistry analyzers, which thereby widens the scope for ... of geriatric and bariatric population, which is highly susceptible ...
(Date:3/27/2017)... Calif. , March 27, 2017  Impax Laboratories, ... has appointed Paul M. Bisaro as Impax,s ... the Company,s Board, effective March 27, 2017. Mr. Bisaro ... served as Interim President and Chief Executive Officer since ... of generic and branded pharmaceutical experience, Mr. Bisaro, 56, ...
(Date:3/27/2017)... -- Invivotek, LLC, a Genesis Biotechnology Group ® ... contract research organization (CRO), announced the completion of the ... research facility in Hamilton, New Jersey ... source to reduce costs and lessen the CRO facility,s ... Farm follows Invivotek,s recent expansion from a 19,712 square ...
Breaking Medicine Technology: